Studies of Wave-Particle Interactions for Interstellar Pickup Ions in the Solar Wind

该提议者最近在适合遥远赤道日球层的条件下，模拟了星际拾取质子的散射，包括波色散和多重共振。这种散射产生的波浪能被用来驱动湍流级联，通过耗散加热太阳风质子。尽管该模型再现了旅行者2号观测到的大部分粒子温度行为，但在最大径向距离处的结果显示，温度过高，这表明该模型需要改进。PI现在计划对这些波粒相互作用（影响湍流的演变，主导外日球层的能量波动，并决定星际吸收离子对太阳风环境的影响）进行几项新的研究，同时改进模型对湍流的处理。PI将在他的赤道模型中将热效应纳入共振波的色散中。然后，他将扩展该模型对色散共振散射的处理，以包括由非方位磁场中的拾取产生的向内和向外传播波的不等强度。这种更一般的分析将允许在所有的日经纬度对湍流演化进行建模。PI还将把这种新的色散分析应用于准径向磁场中拾取离子的行为，以解决与原位拾取离子观测相关的零星波产生和不完全俯仰角散射的问题。

The proposer has recently modeled the scattering of interstellar pickup protons, including wave dispersion and multiple resonances, under conditions appropriate to the distant equatorial heliosphere. The wave power generated by this scattering was used to drive a turbulent cascade which heated solar wind protons through its dissipation. Although the model reproduced much of the particle temperature behavior observed by Voyager 2, the results at the greatest radial distances showed too much heating, indicating that model improvements were needed. The PI now plans several new studies of these wave-particle interactions (which influence the evolution of turbulence, dominate energy fluctuations in the outer heliosphere, and determine the effect of interstellar pickup ions on the solar wind environment), while improving the model's treatment of turbulence. The PI will incorporate thermal effects into the dispersion of resonant waves in his equatorial model. He will then extend the model's treatment of dispersive resonant scattering to include the unequal intensities of inward and outward propagating waves produced by pickup in a non-azimuthal magnetic field. This more general analysis will allow the modeling of turbulent evolution at all heliolatitudes. The PI will also apply this new dispersive analysis to the behavior of pickup ions in a quasi-radial magnetic field, in order to address questions concerning sporadic wave generation and incomplete pitch-angle scattering associated with in situ pickup ion observations.